DIET.—The prevention of the accumulation of azotized matters in the blood involves, first, a consideration of the question of the diet appropriate to the gouty dyscrasia. The almost uniform counsel upon this point of all the authorities from Sydenham to the present time is, that albuminous foods should be sparingly allowed in the diet of the gouty patient, and that vegetable foods, especially the farinaceous, should constitute the principal aliment. This counsel is based upon the theory that uric acid is the offending substance, and, this being the outcome of a nitrogenous diet, the nitrogenous element in diet must be reduced. My own observation has led me to believe that while this may be a legitimate deduction from the uric-acid theory of gout, it is not supported by the results of clinical experience. If there is one signal peculiarity in the digestive derangements of gouty persons, it is their limited power to digest the carbohydrates, the sugars and starches. In whatever form these foods are used, they are more commonly the source of the dyspeptic troubles of sufferers from gout than the albuminous foods. They provoke the acid and flatulent dyspepsia which so generally precedes the explosion of the gouty paroxysm; and it must have attracted the attention of every observer who has studied the dyspeptic disorders of sufferers from inherited gout, who have sought to control their unhappy heritage by abstemious habits, that these disorders are especially provoked by over-indulgence in saccharine and amylaceous foods.

It is not possible to explain satisfactorily why the lithæmic condition should be induced by the carbonaceous aliments, but we believe there can be no question as to the fact. If, as modern physiological investigations tend to show, the liver is the organ in which urea as well as glycogen is formed, it may be that the overtaxing of its functions manifests itself more readily in the conversion of the albuminous than in that of the carbonaceous foods; or it is possible that the carbonaceous foods are destined chiefly for the evolution of mechanical energy, and that when this destiny is not fulfilled through indolence and imperfect oxygen-supply, they escape complete combustion, and so vitiate the blood. But whatever may be the cause of this anomaly, the clinical fact remains that in gouty persons the conversion of the azotized foods is more complete with a minimum of carbohydrates than it is with an excess of them—in other words, that one of the best means of avoiding an accumulation of lithates in the blood is to diminish the carbohydrates rather than the azotized foods.

The diet which a considerable experience has led me to adopt in the treatment of the gouty dyscrasia is very similar to that which glycosuria requires. The exclusion of the carbohydrates is of course not so strict. Abstinence from all the fermented preparations of alcohol is perhaps the most important restriction, on account of the unfermented dextrin and sugar which they contain. This restriction accords with the common experience respecting the part which wine and beer play as predisposing causes of the gouty disease and as occasional exciting causes of gouty lesions.

Next to the fermented liquors, the use of saccharine food in the diet of gouty persons needs to be restricted. This limitation also is one which common experience confirms. Sweet foods cannot be said to be as provocative of the dyspeptic derangements of the lithæmic subjects as wine and beer, but they are certainly often responsible for the formation of the dyscrasia and for perpetuating many most distressing ailments. Their more or less strict prohibition may constitute the essential point of treatment not only in controlling the progress of the constitutional vice, but in subduing some of the most rebellious lesions. It is important to observe that this prohibition sometimes involves abstinence from sweet and subacid fruits, in the raw as well as in the preserved state. Paroxysms of articular gout have been known to follow indulgence in strawberries, apples, watermelons, and grapes, and the cutaneous and mucous irritations which follow even the most moderate use of these fruits in some gouty persons are certainly not uncommon.

Next in order to the saccharine foods as the source of indigestion in gouty persons come the amylaceous aliments. These constitute, necessarily, so large an element in ordinary diet that the limitation of them in the dietary of gouty persons applies, in the majority of cases, only to their excessive use. This excessive use, however, is often observed. There is a popular prejudice in favor of this class of foods, and a corresponding prejudice against the too free indulgence in animal foods. The purely starchy aliments, such as potatoes and the preparations of corn and rice, and even those which contain a considerable portion of gluten, like wheat, oatmeal, and barley, often provoke in gouty subjects a great deal of mischievous and painful indigestion. This feeble capacity for the digestion of farinaceous foods is most frequently observed in the children of gouty parents, and especially in persons inclined to obesity, and in those whose occupations are sedentary and whose lives are passed for the most part in-doors, and they are least common in those whom necessity or pleasure leads to much active muscular exercise in the open air.

The fats are as a rule easily digested by gouty dyspeptics. This is a fortunate circumstance, for the reason that in the anæmia which is frequently one of the consequences of chronic gout the fatty foods are of inestimable value. In cases of persistent and rebellious lithæmia an exclusively milk diet constitutes a precious resource.

The succulent vegetables, such as tomatoes, cucumbers, cauliflower, cabbage, and the different varieties of salads, constitute for the gouty as well as the diabetic subject agreeable and wholesome additions to a diet from which the starchy and saccharine vegetables have to be largely excluded.

The quantity of food proper for gouty persons to consume can only be determined in individual cases by the age, the habits, and the occupation. It is fair to assume that in adults, in whom there is no longer any provision to be made for growth, the daily quantity of food must be regulated according to the amount of energy which is expended. In this energy must be reckoned the amount necessary for the maintenance of animal heat and the other vital functions, and the amount which is necessary for the operation of every variety of nervous force. In other words, the potential energy latent in the food must correspond to the active energy exhibited in the daily evolution of vital, intellectual, and mechanical work. The more nearly this balance is maintained the more closely the physiological standard of health is preserved. That an excess of food is a most frequent cause of the gouty dyscrasia among the well-to-do classes is undeniable, and it is possible that regulation of the quantity according to the rule above mentioned may, after all, be the most important point in the management of many gouty patients. It may be, also, that the reason why the withdrawal of the carbohydrates produces its good effects upon these patients is that we thereby exclude a large amount of force-producing foods which do mischief because they are imperfectly consumed.

EXERCISE.—Next in importance to diet as a hygienic regulation in the management of gouty patients is enforced exercise. The axiom of Abernethy, "to live on a shilling a day, and earn it," comprises the philosophy of the true relations of food to work, and of both to the highest development of physical health. Exercise is to be enforced not simply as a means of securing an active respiration, and thereby an abundant supply of oxygen, but also as a means of converting the potential energy of the food consumed into vital energy. The essential condition, moreover, of healthy nutrition in every organ and in every tissue is the maintenance of a vigorous functional activity. Over-use is not more productive of tissue-degeneration than disuse. Hence the question of exercise in its largest sense involves not only muscular work, but work of all kinds, which tends to promote a healthy activity of the psychical as well as the physical functions. Muscular exercise in the open air has a special value for the victims of this gouty dyscrasia by equalizing the circulation, quickening the respiratory movements, and stimulating the elimination of effete matters from the skin and lungs, but mental work and wholesome diversions are not less important as antagonizing the evil effects of indolence and over-feeding, which are among the common predisposing causes of acquired gout. In persons who are incapacitated by neuræsthenia or by excessive corpulence, the result of long indulgence in indolent and luxurious habits, it may be necessary to resort to passive exercise by rubbing, massage, and electrical excitation in order to secure the good effects of voluntary work.

BATHING.—Another hygienic regulation of great value in the treatment of gouty dyscrasia is the promotion by bathing and friction of the eliminative function of the skin. Daily sponging with cold water, where it is not contraindicated by a feeble circulation and a slow reaction from the shock, is a practice to be commended. Where, for the reasons mentioned, it is not practicable, tepid baths and frictions may be substituted. In cases where the arthritic lesions are progressive and advanced much benefit may be derived from hot baths. It is doubtful whether the thermal alkaline and sulphur spas owe their renown in the treatment of chronic gout so much to the mineral ingredients of their springs as to their high temperature. The Russian and Turkish baths furnish most efficient means for increasing the functional activity of the skin, but they often have a depressing effect on the action of the heart, producing faintness and dyspnoea, and should always be advised with caution.

CLIMATE.—In rebellious forms of the gouty dyscrasia a warm climate is unquestionably a hygienic condition of great value. The geographical distribution of gout, which shows that the disease is much less common in warm than in temperate and cold climates, while it may not perhaps be wholly explained by temperature alone, is very certainly largely due to it. The possibility of out-door life and the increased functional activity of the skin which warm climates favor are circumstances more or less antagonistic to the development of the gouty diathesis.

MEDICINAL TREATMENT.—The objects to be aimed at in medicinal treatment of the gouty dyscrasia are—

1st, the improvement of the primary digestion.

2d, the relief of the gastro-intestinal catarrh, which is the cause of the direct and reflex dyspeptic symptoms which belong to this diathesis.

3d, the augmentation of food-oxidation, so as to secure its thorough combustion.

4th, the promotion of the elimination of the waste products of nutrition.

1. The improvement of primary digestion—or, as it has been aptly called, exterior digestion—often requires very strict attention beyond the proper selection of alimentary substances. The distressing symptoms that indicate primary gastric and intestinal indigestion are certainly often relieved by the rigid exclusion of certain articles of diet, but in many cases it is necessary to assist the preparatory processes which are essential to perfect food-absorption by artificial methods based upon the knowledge derived from physiological experiment. To no one is the knowledge of these methods more largely due than to Roberts of Manchester. Preparations of pepsin and pancreatin, by which the proteids and starches are peptonized and the fats emulsified, are often of inestimable value in the treatment of gouty dyspepsia. Pancreatin, especially, which by means of its trypsin, diastase, and emulsive ferment possesses the threefold property of aiding the digestion of the azotized, amylaceous, and fatty elements of food, is certainly the most valuable of the artificial means for augmenting the efficiency of primary digestion.

2. The relief of the gastro-intestinal catarrh in gouty dyspeptics may often be accomplished solely by dietetic restrictions and by the aid which may be given to primary digestion. It is often necessary, however, to direct some special medication toward the relief of the catarrhal lesion. The circumstances which demand this special medication are the existence of portal congestion, the result of functional derangement, or of chronic atrophy of the liver, or of chronic diffuse or interstitial nephritis, or of cardiac disease. The hydragogues, such as calomel, podophyllin, colocynth, and other vegetable cathartics, with the salts of sodium and magnesium, constitute the most common and efficient means of relieving portal congestion, whether it arise from temporary functional derangement or from organic disease. The renown of some of the more famous mineral springs in relieving the miseries of gouty sufferers is due mainly to the relief of portal congestion and the washing away of the catarrhal mucus which obstructs the process of primary food transformation and absorption. This is especially true of the sulphate of sodium waters, like those of Carlsbad, Marienbad, Friedrichshall, Pullna, and Hunyadi János. While the value of these waters in chronic gout is unquestionable where their use is properly regulated, there is good reason to believe that their long-continued employment is often harmful by relaxing the mucous membrane, and thereby tending to aggravate the condition they are given to relieve. This is markedly true of their use in weak and anæmic persons. For these the milder magnesian waters, such as those of Kissengen, Hombourg, Wiesbaden, and Saratoga, are to be preferred.

3. The augmentation of food-oxidation may be accomplished in a large degree by regulation of the diet and by out-door exercise. The regulation of the diet according to the occupation and habits of life is a point of primary importance in securing proper blood-elaboration. My experience leads me to believe that the evil consequences of in-door occupations and sedentary habits are most common in those who live upon a diet composed largely of starchy and saccharine foods, and that a diet in which animal foods and fats predominate is best suited to indoor workers, whether they be engaged in mechanical or intellectual labor.

The medicines which help to promote the oxidation of the food-elements, especially the carbohydrates, are alkalies and iron. Clinical observation establishes this fact as strongly in the treatment of gout as in that of glycosuria. The relative power of the salts of potassium and sodium in augmenting oxidation is not clearly determined. The salts of sodium appear to be most useful in aiding the process of primary digestion, and the potassium salts in improving the process of sanguification. It is well known that potash predominates in the corpuscles and soda in the serum of the blood. The efficacy of the combinations of iron with the salts of potassium, as in Blaud's pills and in the citrate and tartrate of iron and potassium, in the treatment of anæmia, is well known. In the most renowned ferruginous springs, however, such as those of Schwalbach, Spa, Pyrmont, and St. Moritz, the iron is combined with salts of sodium, calcium, and magnesium. It would appear, therefore, that the increased energy of iron in augmenting hæmatosis, when combined with alkalies, is not relatively greater with potash than with either of the other alkaline bases.

4. The promotion of the elimination of the waste products of nutrition is to be accomplished by remedies which act as solvents of uric acid and as diuretics. As solvents of uric acid the salts of lithia and potash have been shown to be superior to those of soda. The urate of lithia is the most soluble of the uric-acid salts, and the low chemical equivalent of the metal lithium makes the neutralizing power of the oxide much greater than that of equal proportions of the other alkalies. It is used in the forms of carbonate and citrate, and is generally combined with potash and soda. It exists in some of the mineral springs of Europe and of this country, but in such minute proportion as probably to be of little value. In administering the salts of potash and soda it is generally admitted that the carbonates and the neutral salts of the organic acids are to be preferred to solutions of the caustic alkalies. They have less power in neutralizing the acid of the gastric juice, and enter the circulation as neutral salts, where they are decomposed into alkaline carbonates by the oxidation of the organic acids, increasing the alkalinity of the serum and acting as diuretics. The combinations of the alkalies with sulphur, with iodine, and with mineral acids, as in the alkaline springs, are frequently used in the treatment of gouty lesions of the subacute variety. The sulphur salts probably owe their chief value to their alkaline bases when they are used internally; and in sulphuretted baths, as before remarked, the good effects are probably due to the high temperature at which the bath is usually administered.

The salts of iodine are generally supposed to have a special action in removing the consequences of chronic fibrous inflammation in gout and rheumatism. They often disturb the digestion and provoke troublesome irritations of the skin and mucous membranes. In removing the sclerotic effects of gouty inflammation they do not exhibit the same sorbefacient power which they show in their action upon the granulation tissue of syphilitic origin. It must be admitted, however, that in certain catarrhal affections of a gouty nature the iodides of potassium and sodium are almost specific in their good effects. In the pharyngeal, laryngeal, and bronchial catarrhs from which some gouty persons suffer, where there is a dryness and irritability of the mucous membrane, the administration of these salts produces the most prompt and beneficial result. As solvents of uric acid they do not appear to equal the salts of the organic acids.

As to the mode of administering salines in the treatment of the gouty dyscrasia, it is hardly necessary to observe that it must vary with the effect desired. As antacids in acid dyspepsia they should be given soon after meals, and for this purpose the salts of soda are to be preferred, for the reason that they not only neutralize excessive acidity, but they increase the efficiency of the peptonizing process. Where it is desired to introduce these salts into the circulation for their solvent action, as diuretics or to assist the process of sanguification, they should be given three or four hours after meals and largely diluted with water.

Before concluding the consideration of the treatment of the gouty dyscrasia it should be remarked that the ability of water as a solvent, as a means of stimulating tissue-changes and eliminating waste, is not generally estimated at its true value. The use of copious libations of hot water in the treatment of gout, recommended by Cadet de Vaux in 1825, has been revived from time to time, and is at present attracting considerable attention.

TREATMENT OF ACUTE ARTICULAR GOUT.—There are three distinct methods of managing an attack of acute gout—the antiphlogistic, the expectant, and the abortive.

The antiphlogistic method, in the strict application of the term, is practically obsolete. Bloodletting, both general and local, brisk catharsis and diaphoresis, with low diet, were formerly advocated as the natural and imperative antagonists of gout as well as of all other acute inflammatory affections. Carried to its extreme degree, this method was deprecated by Sydenham and his disciples as tending often to prolong the attack and precipitate the manifestations of atonic gout. The natural reaction from the vigorous antiphlogistic practice was what has been termed the expectant method.

The expectant method may be said to be founded upon the aphorism of Mead that "gout is the cure of gout." The discovery of the salts of uric acid in the blood-serum and in the affected tissues gave a scientific basis to the humoral pathology of gout and led to the formulation of definite principles in the application of the expectant method of treatment. These principles are the prevention of the further accumulation of the urates in the blood and the promotion of their oxidation and elimination. The first principle involves restriction to a rigid diet during the attack, excluding albuminous foods and the fermented preparations of alcohol, and allowing only milk and farinaceous gruels. The oxidation of the urates is encouraged by the administration of alkalies and by an abundant supply of air, the inhalation of oxygen even having been recommended. The elimination of the urates is accomplished chiefly by diuretics and moderate catharsis. The local treatment commonly used with this medication consists in the application of alkaline and anodyne fomentations or of dry flannel or cotton. Local bloodletting and blistering are now rarely commended. Under this treatment the intensity of the inflammatory process is abated, the suffering is allayed, but the progress and duration of the disease are not materially modified. The recovery, however, is satisfactory, and it is claimed that the chances of early recurrence of the attack are diminished. This method has many advocates, though it cannot be said to represent the common practice of the present day. It is becoming traditional, and may be said to be gradually giving place to the specific or abortive method.

The abortive method consists in cutting short the attack by the administration of colchicum, veratria, or the salicin compounds.

The value of colchicum in joint affections is a tradition of the earliest records of medicine. It shares its curative effects in acute gout with veratria, and, though the active principle of the meadow saffron and the veratrum album are not isomeric, their effects are similar. They constitute the basis of the famous nostrums so extensively patronized by sufferers from gout. Colchicum is the active agent in the eau médicinale de Husson, in Wilson's and Reynolds's specifics, and in the pills of Lartigue and Blair, while veratria is supposed to be that of Laville's remedy. The action of these substances is not understood. The physiological action of colchicum is that of a local irritant and a cardiac depressant of great energy. It purges violently when given in large doses, causes nausea and vomiting, and may produce collapse. In therapeutical doses in a gouty paroxysm it acts as a diuretic and an antipyretic, and allays, sometimes in a most magical manner, the objective and subjective symptoms of the disease. As simple purging by other cathartics does not abort the gouty seizure, the value of colchicum cannot be ascribed to its purging effect, and, besides, purging is by no means necessary to its efficiency. Nor can its utility be ascribed to its diuretic property. There is some question in regard to its claims as a diuretic, and there seems to be no doubt that it often does good where this effect is not observed. Its influence upon the heart does not explain its marvellous action upon the local process, for the same influence obtained by other drugs has no such result. We are driven, therefore, to the conclusion that colchicum has a specific action in gout as certain and as inexplicable as that of quinia in malarial fever, or iodide of potassium in constitutional syphilis. For those who accept the theory that gout is a tropho-neurosis the therapeutical action of colchicum is a strong confirmation of its neurotic origin, for the reasons that colchicum has no influence upon arthritic lesions which are not gouty, and that its physiological effects point to its action on the nervous system.

It is useless, however, to speculate on the way in which colchicum and allied substances affect gouty inflammation; the practical question to be determined is: Are they the best and safest remedies to control it? Upon this point there is a wide diversity of opinion. The objections to the colchicum treatment are based upon humoral pathology, and upon the idea that the attack is an effort of nature to cast out the poison and purify the blood. Colchicum, it is claimed, arrests this process; the poison is retained, diffuses itself through the tissues, and lays the foundation of vascular and visceral lesions. It shortens the intervals between the attacks, and tempts the patient to continued indulgence in the habits which perpetuate and exaggerate the disease. The advocates of the abortive treatment, on the other hand, claim that these arguments have no real force as applied to its therapeutical value. The cure accomplished is, to all appearances, complete, and the patient is saved the suffering and exhaustion which result from the expectant method. The fact that he is so easily and speedily cured, and that he resumes his vicious habits and suffers recurring attacks in consequence, proves only that the treatment lacks the quality of moral discipline which belongs to prolonged suffering and the penance of vigorous medication. It is an acknowledged fact that the great majority of sufferers from acute gout decide sooner or later in favor of the abortive treatment; and as professional opinion has heretofore generally advocated the expectant or eliminative treatment, they commonly resort to the use of some one of the quack remedies which contain colchicum or veratria.

In view of the present uncertainty of our knowledge of the true pathology of the acute gouty arthritis, as to whether it is a tropho-neurosis or the result of the local irritation caused by the salts of uric acid, the specific treatment seems to be justified by a regard for the comfort of the patient and as a means of protecting him against falling into the reckless use of quack remedies. A speedy relief of the acute symptoms, followed by the treatment appropriate to the gouty habit, would seem to be the most rational and safest mode of managing the acute articular attacks of gout.

The selection of the preparation of colchicum in the treatment of an acute paroxysm is a matter of individual experience and preference. The acetous extract and the wine of the seeds are most commonly used, and many practitioners are not scrupulous in prescribing the proprietary preparations of Reynolds, Laville, and Blair. The wine of colchicum may be given in doses varying from 20 to 40 minims, alone or combined with Epsom salts in drachm doses, with small quantities of opium, every six or eight hours. Under this medication the pain, tenderness, and swelling rapidly abate, and sometimes with an abruptness that is magical. As soon as the acute symptoms subside, the colchicum should be continued in smaller and less frequent doses until the fever and local tenderness subside. The use of quinia with small doses of colocynth after the colchicum has been discontinued helps to re-establish the strength and regulate the digestive functions. The patient should always be warned against the possible demoralizing effects of a speedy recovery from a serious disease. Recurrence after the colchicum treatment is certainly more common than after the expectant method, but this should not be ascribed so much to a defective cure as to the temptation which the antidote offers to trifling with the poison. The accidents which have been ascribed to colchicum through its causing heart-failure are probably to be explained by its injudicious administration in large doses where acute gout is complicated with cardiac or renal degeneration.

Next in importance and value to colchicum in the abortive treatment of gout are salicin, salicylic acid, the sodium salicylate, and the oil of wintergreen. Unlike colchicum, which has no marked effect upon acute rheumatism, these medicines appear to act with similar energy on gout and rheumatism. The rapidity and the almost uniform way with which they allay the inflammatory symptoms in rheumatic fever are well known; their value as specific remedies in both acute and subacute gout is not so generally appreciated. Whether the specific action of colchicum in gout differentiates this disease from rheumatism, or whether the similar action of the salicin compounds indicates that these diseases are allied in their etiology, are questions yet to be solved. The good effects of salicin and the sodium salicylate in many of the forms of irregular gout, and notably in the dyspeptic disorders and the erythematous tegumentary lesions, are especially worthy of notice. In acute attacks of articular gout the salicylic acid or the sodium salicylate, in 15 or 20 grain doses repeated every three or four hours, will often cut short the attack, and will very certainly allay within twenty-four hours the acuteness of the symptoms. As in rheumatism, the medicine should be continued in smaller doses after the acute symptoms have subsided for several days, the tendency to relapse being marked if the drug be discontinued too soon. In subacute articular gout and in the irregular forms of the disease, where the medicine has to be continued for some time, salicin and the oil of wintergreen are to be preferred to salicylic acid and the sodium salicylate. They are less liable to disturb the stomach and to produce toxic effects.

It is unnecessary to describe the treatment of the different forms of irregular gout, inasmuch as the general principles described in the treatment of the gouty dyscrasia involve the most important considerations in the management of these affections.

RACHITIS.¹

¹ There is a difference of opinion as to the correct spelling of this word, and strong reasons exist to regard the form rhachitis as the proper one. It is true that this spelling of the word has been remarked upon as unorthographical by many, mostly modern, authors. Even Virchow writes "Rachitis," claiming that Glisson took the term from "the then popular rickets." This is a mistake, as H. Rohlffs points out (Deutsches Arch. f. Gesch. d. Med., 1883, p. 294). Rachitis is a Greek word, and was used in the classical time of Hellenism. It has, however, seemed best to preserve here the usual spelling, rachitis, which has become sanctioned by general usage.

DEFINITION.—Rachitis is a general nutritive disorder, almost always of long duration, usually with an introductory stage of weeks or months and a course mostly extending over months or years. Its beginning is mostly gradual, its final recovery slow. It is complicated with or dependent on disorders of the digestive or respiratory apparatuses, which are preceded by a disposition probably created by an undue width of the arteries. It exhibits amongst its prominent symptoms muscular debility; perspiration; anomalies of the subcutaneous tissue, which is either very much infiltrated with fat or deprived of it; disturbances of the intellectual and moral functions, and of those of the large thoracic and abdominal viscera and lymphatic glands; changes in the latter may outlive all others. Its most perceptible symptom, however, consists in an inflammatory disease of the primordial cartilage of the epiphyses, a copious deposit in that region and also under the periosteum of the bones; curvature of the diaphyses, and, while absorption remains intact, softening and retarded ossification of the bone. Without these affections of the osseous system the diagnosis of rachitis is not complete.

ETIOLOGY AND PATHOLOGY.—The nature of rachitis has been considered to be inflammatory by F. A. Walter.² Renard looked for that inflammation in the periosteum. Guérin emphasizes the vascular increase in periosteum, bone, and marrow; Trousseau and Lasègue the congestive character of the local tumefaction, besides fever and pain. Virchow also³ inclines to the opinion that the rachitical process is of an inflammatory nature, though it be impossible to state the exact cause of the process. Still, he claims that we are no better off in regard to other inflammations of unknown character—for instance, those of the skin—and that we have to look for a future increase of our knowledge of such constitutional predisposition of the organism and of such specific qualities of the blood as will produce the local irritation of the osseous tissue in rachitis. Last, and mainly, it is Kassowitz who seeks the essence of the rachitical process in a chronic inflammation originating in the points of apposition of the growing bones of the foetus or infant. During the chronic inflammation blood-vessels are formed in large numbers, and a morbid congestion takes place in all blood-vessels, but mainly in those of the localities in which new bone is forming; thus in the chondro-epiphyses, in the perichondrium and periosteum, and the sutural substances. Faulty introduction or elimination of lime has nothing to do with this process. It cannot be deposited in the current of a copious circulation; in fact, it is not deposited in the immediate neighborhood of blood-vessels to any extent. Even in otherwise normal bone hyperæmia produced by the experimenter softens the bone, which was fully formed before. If the relative percentage of lime were of any account in the etiology of rachitis, the periosteal and cartilaginous proliferations would find no explanation. But why is it that this peculiar process takes place at an early age only? and in the bone only? Kassowitz urges the fact that the growth of the bone differs in this from the development of all other tissues: that the latter grow uniformly through their whole mass; that the circulation in them is more uniform and carries material through and into every particle simultaneously, while in the bones the only places in which the whole circulation can contribute to their growth—the few blood-vessels distributed in the interior not adding to their growth at all—are the periosteum and the places of apposition between epiphysis and diaphysis. Every morbid irritation, whether resulting from bad air, habitation, and food, or from either chronic or acute ailment, acts on the whole mass of other tissues and organs, but in the bones only on the growing ends or surface.

² Anatom. Museum, Berlin, 1796, vol. ii.

³ Arch. f. Path. Anat., vol. v.

The results of the pathologists and experimenters are confirmed by chemical analyses. Fat has been generally found somewhat increased in the rachitical bones, and water largely so; chondrin is diminished according to Marchand and Lehmann, but was found unaltered in the later analyses of A. Baginsky. The latter found, after having deprived the bone of fat, the organic and inorganic material to be in a proportion of 100 to 563 in the normal, and of 100 to 160 in the rachitical osseous tissue; and in 100 parts of dry bone, Gorup-Besanez found in the

Defective calcification of the forming bone is one of the principal characteristics of rachitis. In it lime cannot either enter into the composition of the osseous tissue or remain in it. Its elimination must take place either through the kidneys or the intestinal tract. In the feces Ad. Baginsky, and many before him, have found an abnormal quantity. In regard to the urine, modern investigations do not agree with former analyses. Thus, Baginsky concludes that there is no increase of lime in the urine of rachitical as compared with that of healthy children; Seemann found even a diminution of the percentage of lime. Amongst modern writers only Rehn found an occasional increase of lime in the urine of rachitis.

In regard to the elimination of phosphoric acid, the analyses of different periods do not agree any better. The conclusions of previous researches, pointing to a quadruple elimination of phosphoric acid in the urine of rachitis, are refuted by Seemann, who found no increase, and by Baginsky, according to whose researches the phosphoric acid of the healthy urine compares with that of rachitical urine as 40:12-37.

As far as the elimination of nitrogen is concerned, there appears to be but little difference between normal and rachitical urine. Chlorine was found to be diminished in rachitis by Baginsky. Lehmann and Von Gorup found lactic acid several times. Several times albumen was met with; in a case of Ritchie's, blood; in one of Von Gorup's, fat.⁴

⁴ E. Salkowski und W. Leube, Die Lehre vom Harn, 1882, p. 536.

The etiology of rachitis must be studied from two points of view. It has its predisposition and its direct and proximate causes. The former has been studied by F. W. Beneke⁵ upon an anatomical basis. He finds that the arteries of rachitical patients are large all through the body. This is so particularly in the carotids; it seems probable that the changes taking place in the head are due to this anomaly in the size of the arteries. Three cases in which the width of the arteries of the neck was unusually large terminated fatally—one by hydrocephalus, one with a very large skull, and one suddenly. This width of the arteries is most marked, under ordinary circumstances, from the second to the fourth year; that is, the exact time in which (except the cases of early rachitis) the rachitical process is at its height. It is considered by Beneke to be the cause of the local increase of vascular irritation, particularly in the epiphyses with their retarded circulation; and also of the increase of nutritive development which is so often noticed during recovery from rachitis; and, finally, of the many pulmonary complications of an inflammatory nature.

⁵ Die Anatomischen Grundlagen der Constitutions Anomalien des Menschen, 1878, p. 75, etc.

There is another interesting consideration in regard to the effect of wide arteries on the relations between the blood and tissues. A great many more blood-cells are required to fill the arteries when wide than when narrow. Now, the formation of blood-cells is hindered by any disease of the digestive and blood-preparing organs, so that the tissues are liable to show the relative increase in the percentage of water, which is uniformly confirmed for rachitis by the biochemists.

The pulmonary artery of the healthy infant is larger than the aorta by not more than four millimeters. In the majority of cases of rachitis examined by Beneke this difference in size was very much more favorable to the pulmonary artery; it is abnormally large in rachitis. This anatomical fact is suggestive of the pathological processes so frequently found in the lungs and in the neighboring lymphatic and large abdominal glands. For, while the amount of blood introduced into the lungs through its wide artery is unusually large, particularly so in a chest which is contracted in consequence of the rachitical process in the bones, the exit from the lungs is relatively impeded. Not only, however, the narrowness of the chest is a cause of this disproportion. For even in rather normal chests the lungs of rachitical children are relatively small.

The liver of almost all rachitical children is large. In but one-half of the cases this enlargement is accompanied with a large heart. In pure cases of scrofula, on the contrary, Beneke found a small heart, rather narrow arteries, and usually a small liver, the size of the lungs offering but few anomalies.

The spleen also is large in the majority of cases. Its size is not dependent on the large size of the liver or the small size of the lungs. For these conditions are found in the majority of cases only, not in all of them, and the large spleen is not always found with a large liver and small lungs. The variability of the anatomical conditions permits of various degrees of combination; so that varying combinations of rachitis with other constitutional disorders may correspond with the different sizes of the principal organs. After all, as there is a great deal of independence of these organs, as to size, of each other, the conclusion is justified that those differences are not the result of the disease, but that they are congenital and stand in some causal relation with it.

The kidneys are large in the majority of cases, like the spleen and liver, while the lungs are small. This disproportion is apt to result in a hyperæmic condition of all the organs of the abdominal cavity, and especially of the kidneys. To what extent this undue amount of volume interferes with, or increases, renal secretion, it is difficult to say. The amount of urine secreted by rachitical children is about normal, though, as already stated, the percentage of lime in it is rather diminished, contrary to the opinions held formerly.

For the direct cause of rachitis Glisson looked to the inequality of nutrition by the arterial blood, and for that of the curvature of the long bones to their superabundant vascularization. He found the disease mainly amongst the well-to-do classes, not unlike a modern American writer, who declares infantile paralysis to be the result of the nervousness of the better classes of the American people! John Mayow (1761) held a disturbance of the innervation responsible; Zeviani (in the same year), improper food in general, and particularly prolonged lactation; and Selle (1791), a peculiar diathesis (acrimonia rachitica). About that time a defective nutrition with abnormal function of the lymph-ducts was looked upon as the cause of rachitis by many—by others, an undue production of acid, and the softening of the osseous tissue thereby. This result was attributed by some to the influence of milk (Veirac, De Krzowitz). Attention was directed at an early time to phosphoric acid and lime, with the view that variations in the elimination of these substances might explain the occurrence of rachitis. A large quantity of both was found in some urines (Malfatti); a superabundance of phosphoric acid was presumed to prevail in the whole system (Wendt, Fourcroy); while symptoms resembling rachitis were found in animals fed upon small doses of phosphoric acid by Caspari (1824). Chossat fed young animals on food deprived of lime, and claimed to produce softening of the bones and death, a result which was denied by Friedleben. Guérin claimed to produce rachitis by feeding young animals on meat in place of their mother's milk, a result equally denied by Tripier, who, like Friedleben, found the bones under such circumstances more liable to fractures, but not rachitical. Wildt and Weiske found the bones uninfluenced by withholding lime from food; Forster, however, and Roloff claimed to notice a marked influence, and the latter stated that animals, after having been rendered sick by depriving them of lime, recovered when they were again supplied with it. Wegner, in his numerous experiments with phosphorus, found that in growing animals it increases the growth and firmness of both long and flat bones; after the growth of the animal has been completed it renders epiphyses and vertebræ denser. There is no change, however, in the relative chemical composition of those parts. He found at the same time that results similar to those caused by the administration of phosphorus were obtained when food deprived of its phosphate of lime was given. But he met with no rachitical changes proper during these several procedures. Teissier having found an increase in the urine of rachitis after the administration of lactic acid, and lactic acid having been frequently found in the urine of rachitical patients by Ragsky, Morehead, Simon, and Lehmann, C. Heitzmann fed with lactic acid both carnivorous and herbivorous animals, found the cortical layer of the bones softened and the medullary substance hyperæmic, and claimed to produce rachitis in the former and osteomalacia in the latter. Both of these assertions were denied by Tripier and Toussaint, who insist upon Heitzmann's having selected animals which have a peculiar disposition to suffer from rachitis. Again, Milne Edwards and Boussaingault found the bones softened when they withdrew both phosphoric acid and lime from the food, without restoring the bone's consistency by administering powdered bone. But, lately, Ad. Baginsky states that he produced rachitis by withholding lime, and increased the effect by introducing lactic acid. By so doing, however, he changed only the relation of the mineral to the organic substances, without interfering with the normal proportions to each other of the constituents of the ashes. Beneke, finding oxalic acid in the urine in many cases of rachitis, attributes to it the want of calcification in rachitis, and Senator suggests that what impedes the deposition of bone might be formic, acetic, and lactic acids, which are also found in the young osseous tissue.⁶

⁶ L. Fürth, Path u. Ther. d. Rachitis, Wiener Klinik, 1882.

Of these statements many are uniform, others contradictory. Thus far, they are not convincing except in one way—viz. that both withholding and introducing certain ingredients, mainly lime, influence the growth of the bone considerably. This may prove nothing else but that lime is of paramount importance in the building up of bone, and that bone in the period of rapid development is amenable to a great many influences.

It is in the period of rapid development that rachitis is observed. Thus it occurs in every stage of intra-uterine and infant life. It is met with in the foetus in very early intra-uterine life; it is found as a congenital affection, continuing to develop after birth when it has originated in the latter half of foetal existence; there is, thirdly, the rachitis of early infancy; and, lastly, that of advanced infancy and childhood. Of 624 cases of rachitis enumerated by A. Baginsky, there were 256 less than a year old, 313 in the second, and 63 in the third year. After this time rachitis is rare, as far as the active symptoms of the disease are concerned. But still, a retarded form of rachitis (r. tardiva) has been described by some authors. It is said to occur about puberty, and to exhibit local changes in the bones of genuine rachitical character, but to be wanting in all the other symptoms required for the diagnosis of general rachitis. Such cases have been described by C. Lucas.⁷ He found it complicated, now and then, with albuminuria. The occurrence of the latter at that time of life had been referred to by Moxon.⁸ The principal symptoms described by Lucas are scoliosis, talipes valgus, and genu valgum. The epiphyses were slightly thickened; there were pain in the limbs, languor, and pallor. In some of the cases there were also rachitical deformities dating from infancy. He believes rachitis of adolescence to exhibit more symptoms belonging to relaxation of the ligaments than to softening of the bones.

⁷ Lancet, June 9, 1883.

⁸ Guy's Hosp. Rep., 1878.

A case of rachitis of undoubtedly congenital nature has been reported by Chiari. There were but twelve teeth. There were no other alveoli, nor was there any intimation of the formation of alveoli in the shape of the jaw, which resembled very much the usual senile form of retrograde metamorphosis.

Twenty years ago I described the lesions in part of a rachitical cranium removed from an infant who lived up to her eleventh day. She was born at full term with hernia of the brain, about one-sixth of which protruded through the small fontanel. Only the cranium could be studied with regard to rachitis, and but small portions of the frontal and the anterior half of the parietal bones surrounding the large fontanel could be removed. In these few square inches of bone there were between twenty-five and thirty openings of the usual craniotabic nature, nothing but a transparent membrane being left. The bony edges of these thin portions were partly sloping off gradually, partly very steeply, and somewhat thickened. They were distributed over the whole part of the skull removed; some were found in the immediate neighborhood of the points of ossification. No recent deposits of soft rachitical bone had taken place under the periosteum. Thus, evidently, the process was of rather an early date of intra-uterine life, and had at birth run the full course of its usual development without having had an opportunity to terminate in the restitution of the normal bone.⁹

⁹ Amer. Jour. Obst., Nov., 1870.

In a case reported by Dr. F. A. Burrall¹⁰ the infant (female) was cyanosed at birth, and had a small head and feeble general development. The respiration was shrill and piping from birth, as though from congenital laryngismus; in a few days it became raucous. The post-mortem examination proved the larynx normal, with no obstructive growths. She was pigeon-breasted, and the last phalanx of her right finger wanting.

¹⁰ Trans. N.Y. Path. Soc., vol. i. p. 81.

In the meeting of June 27, 1883, of the Société de Chirurgie of Paris, Guéniot presented a newly-born baby with well-pronounced rachitis of the extremities which had healed at the time of birth. The bones had recovered their firmness, and the characteristic deformities remained. In the meeting of December 19th he could report that the child had exhibited neither symptoms of rachitis nor of syphilis since. In regard to the latter, a very rigorous examination of the baby's whole family, made by Guéniot and Fournier, resulted in the existence of no trace of syphilis.¹¹

¹¹ Rev. Mens. des Mal. de l'Enfance, Janv., 1884.

Kassowitz has examined many still-born infants, and also children dying at an early age, at the foundling hospital of Vienna. In a large majority of the cases he found rachitical changes in the ends of the bones. In many of those who lived several weeks he found rachitis developed to such an extent that the presumption of its intra-uterine origin became conclusive. Here nothing is left but the conclusion that the cause of congenital rachitis has to be looked for in the condition of the maternal blood.

Thus, the foetal and congenital occurrence of rachitis cannot be doubted. Both forms are represented in literature. Neither requires the presence of rachitis in one or both of the parents. But the cause of the intra-uterine disease has not been found. Perhaps a disease of the mother with considerable nutritive disorders or a defective placentar supply may be found responsible. The foetal form runs its course long before the normal termination of pregnancy; the congenital may have run its full course at birth or complete it afterward. The bones are found of characteristic nature, the diaphyses suffering more than the epiphyses; even a rachitical pelvis has been met with by Fischer. Early foetal rachitis is probably dependent upon a defective development of the very first cartilaginous deposits and the first osseous nuclei; thus, many of the congenital synostoses find a ready explanation. Besides these, abnormal circulation is accounted for. For periosteal proliferation at that early period contracts the foramina carrying the blood-vessels, and, while interfering with the size of the bones, the foramen magnum also. Thus, a certain class of cretinism appears to be due to foetal rachitis, mainly of the base of the cranium, which results in early ossification of the synchondroses, particularly of the sphenoid bone. But lately I have seen a case of this description, which, however, had not terminated at the time of birth. For after birth the rachitical process developed further, and in addition to the rachitical deformity of the base of the cranium there were afterward thickening of the epiphyses, pigeon breast, and thoracic grooving and flattening.

Rachitis is found in city and country, less on mountains than in valleys. Still, it is met with at elevations of two thousand feet. In the tropical regions it is almost unknown. Why it should have been considered quite a new disease in England but a few centuries ago, or whether it did not exist before that time, it is difficult to say. It is certain, however, that deformities have been described in antiquity which we are accustomed to attribute to rachitis.

As the disease is one that occurs during the period of rapid growth, and is a developmental disease, everything that interferes with normal growth and development is apt to change physiological functions into pathological conditions and to produce rachitis. In the pregnant mother her ill-nutrition and the defective cell-material used in the building up of the embryo and foetus, or a defective placenta, may come in for the explanation of foetal and congenital rachitis, although the case of Klein's, who reports twins, of which one was normal and one rachitic, is rather difficult to explain on that basis only. Even rachitis of early infancy is not easily accounted for otherwise, for its first symptoms show themselves at a very early period; thus constipation, adiposity, and afterward craniotabes and thoracic grooving.

The common form, and that which is the usual subject of the text-books and monographs, has, however, in most cases a well-marked preparatory stage in the shape of diseases or ailments reducing sanguification and nutrition. Some cases are ushered in by, or follow the course of, acute exanthems or acute gastric disorders or the presence of entozoa. A larger number appear to result from insufficient oxygenation resulting from lung diseases, with a long chronic ailment following the acute stage. Even acute pneumonia, with its direct influence on general nutrition, stands often for the proximate cause of rachitis. Bad air alone, even swamp air, does not appear to be a sufficient cause. When it seems so, it is complicated with the main cause of rachitis; that is, bad, insufficient, improper food, with its immediate result—viz. intestinal catarrh. Cow's milk, particularly when acid, starchy food administered too early or in too large quantity or too exclusively, early weaning followed by improper artificial food, insufficient mother's milk or such as is either too thin or too caseinous, lactation protracted beyond the normal limit,—may all alike be causes of intestinal disturbances and rachitis.

Is rachitis hereditary? A number of women who were rachitical themselves have been known to have rachitical children. But it has been said that the process runs its full course during infancy, and that therefore a direct inheritance of rachitis from mother to child is an impossibility. Still, we must not forget that the consecutive conditions of the parents may, or will, influence the general condition of the infant and result in similar disturbances. No rule, however, exists. Dyscrasic parents may have healthy children, and healthy parents sickly or dyscrasic ones. But the probability is greater that diseased children should come from dyscrasic parents than from healthy ones. Tuberculosis in the parents has frequently been accused of being the cause of rachitis in the infant—not directly, but in consequence of general impairment of the tissues. Gout has also been accused of being the cause of rachitis, but it is a peculiar fact that the poor have but little gout and a great deal of rachitis. In all of these cases it is better to look upon rachitis as only one of the forms of general mal-nutrition, and to speak of inheritance of the disposition rather than of the disease. Thus it was that about the end of the eighteenth century Portal spoke of scrofulous, syphilitic, scorbutic, rheumatic, arthritic, and exanthematic rachitis. Particularly has syphilis been accused of being the main cause of rachitis by some, and even the only cause by others. Thus it was looked upon by Boerhaave. In modern times Parrot maintained, from 1872 up to the time of his death, which occurred recently, that every case of rachitis is of syphilitic origin. As his proof he relied mainly on the condition of the teeth and the bones. But those appearances in the teeth, the thin and ragged edges, the friability and the grooving, either horizontal or vertical, which have been considered characteristic of syphilis by Hutchinson and others, have no such dignity, and moreover they are not observed in the temporary teeth at all, but in the permanent only; the rachitical softening of the bones also is not found in syphilis at all. Particularly are there no curvatures in syphilis and no infractions. It is true that marasmus is found in both rachitis and syphilis, but it is met with in all sorts of diseases. The changes in the bones of syphilis are found at birth; in rachitis they usually develop in later months. When a baby is syphilitic and rachitic at the same time, the syphilis may last very much longer than the rachitis, which meanwhile has healed. The internal organs in rachitis do not exhibit any such changes as are known to occur in very many cases of syphilis. No gummata are ever found in rachitis, and the interstitial inflammation of the internal organs in syphilis is not met with to the same degree in rachitis. What Parrot claimed as a desquamative syphilide of the tongue—that is, red insulated spots, denuded of their epithelium, small in the beginning, later extending backward and increasing in size—is by no means always syphilitic, but is found in a great many cases where there is no suspicion of syphilis. It is mainly Kassowitz and Bouchut who have taken the stand against Parrot. The former, taking rachitis for a peculiar inflammatory process, admits that syphilis can be one of the causes. The latter directs attention mainly to the fact that by changing food in certain ways rachitis may be produced in dogs, but that they cannot be made syphilitic. There is no doubt, however, that syphilis may give rise to rachitis by its general influence on nutrition, and in this fact lies the key to the connection of great nutritive disorders with each other. Syphilis will undoubtedly change nutrition to such an extent as to result in rachitis. Rachitis will affect the glands; the caseous and suppurative degeneration of the glands will lead to metastatic processes, to acute tuberculosis, and so on.

Malaria been claimed as the main cause of rachitis by Z. Oppenheimer,¹² or, rather, rachitis is presumed by him to be the form in which malaria makes its appearance in young infants. After disposing of other alleged causes of rachitis, none of which is proved to give rise to every case, and referring to the anatomical belief that the peculiar hyperæmia and inflammation of rachitical bones is created by the embryonic condition of the growing osseous tissue, he points to the prodromi, amongst which he emphasizes chronic diarrhoea and the nocturnal crying. The latter, with its perspiration and subsequent sleep, he claims as evidence of malaria, and as a substitute for the intermittent neuralgia of adults, the more so as he believes he finds the spleen tumefied. The persistent diarrhoea of these infants is said to be paroxysmal—to take place in the morning, contrary to what is seen in the usual form of intestinal catarrh; the discharges are said to be serous, not tinged with bile; the appetite to be good through the rest of the day; the weight of the body not to be lessened, but anæmia to develop gradually, and fever to occur occasionally. In other cases infants have cold hands and feet and blue lips toward evening; the skin is pale, the spleen enlarged; otherwise there are perhaps no symptoms, but the infants try to get uncovered, and have an increase of temperature of from 1° to nearly 3° F., and a perspiring head in the morning. After a while the rachitical symptoms belonging to the bones and the general system become apparent. After all of the author's ingenious and emphatic assertions and deductions, it becomes evident that malaria—in the severe forms in which it has been found by Arnstein, Browicz, and Henck to cause bone diseases—may give rise to rachitis, but it is also clear that he tries to prove too much. The long series of attempts at proving that every form and case of rachitis depends upon a single and uniform cause have proved futile. The physiological hyperæmia of the bones and the rapid growth of all the infant tissues are shaped into the complex ailment which we call rachitis by more than a single disease or a single nutritive disturbance.

¹² D. Arch. f. klin. Med., xxx., 1881.

SYMPTOMS.—Before entering upon a more accurate and elaborate enumeration of the symptoms of rachitis, I mean to dwell upon peculiar differences which take place according to the age in which the disease makes its appearance. Very young babies—that is, infants of a month or two—develop rachitis in such a manner that many cases are overlooked until it is too late to relieve them in time. This occurrence takes place when there are no prominent causes, such as diarrhoea or other nutritive disorders, nor any premonitory symptoms. Such infants appear to be perfectly well; they have the average weight, and even more; they have plenty of adipose tissue, and look well. The only anomaly appears to be an undue degree of paleness. Without pain or flatulency they are constipated. This constipation is not congenital, as it always is when the colon is unusually long even for an infant, and when the sigmoid flexure is of double or even treble length, but makes its first appearance about the end of the first or the beginning of the second month. It is relieved only when the increasing muscular power of the intestine results in more effective peristalsis. The second symptom is the thoracic groove, to which I shall allude later, and a gradual thickening of the costo-cartilaginous junctures, with or without periosteal pain on pressure. About the same time the cranial softening, craniotabes, with its hyperæmia and perspiration of the entire scalp, and baldness, and the first symptoms of maxillary rachitis, become perceptible. During all this time the epiphysial swellings and the diaphysial curvatures develop but very slowly; but at a very early time chronic bronchial catarrh, with a loose cough, begins to be troublesome. When rachitis begins at a late period—say, about the sixth or eighth month—the aspect of the case is different. The infant has suffered before either from bronchitis and broncho-pneumonia, or in most cases from indigestion and intestinal catarrh. There is some degree of emaciation; the skin does not fit the limbs, as it were—is loose, thin, flabby, and rather dry. The tendency to diarrhoea continues to prevail. The epiphyses, particularly of the lower extremities, are thickened at an early time, curvatures of the tibiæ become apparent, and all the rest of the bones participate in the process, with the exception, sometimes, of those of the head.

The head, however, is liable to exhibit symptoms of rachitis at a very early period of life. It is large, or appears to be so,¹³ mostly for the reason that the face is proportionately small. The forehead is large, the frontal protuberances very prominent, as are also those of the parietal bones. Thus, the head is more or less square. Dilated veins are visible in and through the pale skin; there is but little hair, on the occiput less than on the rest of the head. Sometimes the occiput is quite bald, the hair having been rubbed off on the pillow. The scalp feels warm, except during perspiration. The latter is very copious, particularly on the occiput—to such an extent, indeed, that the pillow is drenched—and will remain so for months. The sebaceous follicles are often still larger and more numerous than they normally are at that age, and seborrhoea is often, though not always, met with. The sutures are wide, sometimes one or two centimeters; the posterior fontanel remains open; the large anterior fontanel is very large, being sometimes several inches long and wide. The pulse is felt very distinctly through it. The systolic cerebral murmur, which was first found by Fisher of Boston in 1833, and considered to be a positive symptom of rachitis (which certainly it is not, as it is found in almost every healthy baby with a patent fontanel), is very audible. The fontanel and sutures remain open for a long period. Instead of closing, as they do normally at the fourteenth or fifteenth month, the former ossifies about the end of the second or third year, or later. Gerhardt reports a case in which it persisted to the ninth year. The cranial bones appear to be thin, and give way under the pressure of the finger. Ordinarily, it is true, the cranial bones of every baby, even if perfectly healthy, are movable under pressure, but they are so only along the sutures, where they may retain this mobility, in some instances, a long time. Indeed, it appears that sometimes about the middle of the first year the occipital bone becomes thinned out in apparently quite healthy children. Moreover, even in the skulls of infants who were taken to be in good health small defects in the bones were found (Friedleben), with no uncomfortable symptoms at all. Therefore it is rather difficult to draw the exact boundary-line between the healthy and the morbid condition; thus it is possible that some of those cases which exhibited apparently morbid local changes without morbid symptoms may not have been diseased after all. In those, however, in which rachitis is really developed in the cranium a peculiar condition is found. In the posterior half or third of the parietal bones, either the right or the left side being more marked, there are in the tissue of the bone distinct spots in which the osseous material is not only thinned out, but has entirely disappeared. In fact, the bone is perforated, the edges of the holes being rather steep, sometimes slightly thickened, and the scalp separated from the brain only by a thin, transparent membrane, the remnant of the periosteum. These holes can be easily found through the integument. The finger, though ever so gently pressing down upon it, moves the cranium, if any be left, before it; the bone feels like paper, and the sensation as if it could be easily broken through is quite distinct and embarrassing. Such perforations are usually quite numerous; from five to twenty or more can often be counted. They are surrounded by normally hard bone, and thereby can be recognized from the flexible part of the cranium extending along the sagittal and lambdoid sutures. Where these results of rachitical softening, craniotabes, are most prominent—that is, on the part on which the infant is mostly reclining—the bone is flattened, and may remain so for life, though in the majority of cases the asymmetry will disappear. The flattening and perforations result from the same causes—viz. softening of the bones and pressure upon the bone between the pillow outside and the brain inside. With it go, hand in hand, thick rachitical deposits under the hyperæmic periosteum of other portions of the skull. Where craniotabes is largely developed on the occipital portion, the frontal and the parietal bones (in their anterior halves) are usually thus thickened. A cross-section with a knife will reveal a diameter of the new osteoid material between the periosteum and bone of one-half to one centimeter in thickness. It is very hyperæmic—even more so than the bone itself, which, when cut into, exhibits an unusual amount of blood. Sometimes the deposits are still larger, and are apt to change the appearance and weight of the skull considerably after recovery has taken place and eburnation and sclerosis have taken the place of the normal osseous tissue.

¹³ Boötius (1649), quoted by Haller (Bibl. Med. pract., 1779): "Infantibus caput grandescit, reliquum corpus contabescit, ossa in articulis tument, dextrum hypochondrium tumore æquali prominet; hoc malum multis millibus infantum molestum est" ("The infant head grows large, the rest of the body emaciates, the articular bones swell, the right hypochondrium is raised by a uniform tumor; this malady is a sore affection in many thousands of infants").